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The valve is equipped with a service port. There is no
schrader valve installed in the liquid line service port. A ser
vice port cap is supplied to seal off the port.
The liquid line service valve is a front and back seating
valve. When the valve is backseated, the service port is not
open.The service port cap can be removed and gauge
connections can be made.
To Access Service Port:
1− Remove the stem cap. Use a service wrench
(part #18P66, 54B64 or 12P95) to make sure the ser
vice valve is backseated.
CAUTION
The service port cap is used to seal the liquid
line service valve. Access to service port
requires backseating the service valve to
isolate the service port from the system. Failure
to do so will cause refrigerant leakage.
IMPORTANT
A schrader valve is not provided on the liquid line
service port. Valve must be backseated to turn off
pressure to service port.
2− Remove service port cap and connect high pressure
gauge to service port.
3− Using service wrench, open valve stem (one turn
clockwise) from backseated position.
4− When finished using port, backseat stem with service
wrench. Tighten firmly.
5− Replace service port and stem cap. Tighten finger
tight, then tighten an additional 1/6 turn.
To Close Off Service Port:
1− Using service wrench, backseat valve.
a − Turn stem counterclockwise.
b − Tighten firmly, but do not overtighten.
To Open Liquid Line Service Valve:
1− Remove the stem cap with an adjustable wrench.
2− Using service wrench, backseat valve.
a − Turn stem counterclockwise until backseated.
b − Tighten firmly, but do not overtighten.
3− Replace stem cap, finger tighten then tighten an addi
tional 1/6 turn.
To Close Liquid Line Service Valve:
1− Remove the stem cap with an adjustable wrench.
2− Turn the stem in clockwise with a service wrench to
front seat the valve. Tighten firmly.
3−
Replace stem cap, finger tighten then tighten an addi
tional 1/6 turn.
2 − Suction Line (Seating Type) Service Valve
A full service nonbackseating suction line service valve is
used on all early HS26 series units (except 461). Different
manufacturers of valves may be used. All suction line service
valves function the same way, differences are in construction.
Valves are not rebuildable. If a valve has failed it must be
replaced. The suction line service valve is illustrated in
figure 11.
The valve is equipped with a service port. A schrader
valve is factory installed. A service port cap is supplied
to protect the schrader valve from contamination and
assure a leak free seal.
SUCTION LINE SERVICE VALVE (VALVE
OPEN)
FIGURE 11
SCHRADER VALVE
SERVICE PORT
SERVICE
PORT
CAP
STEM CAP
SNAP RING
INSERT HEX WRENCH
HERE (PART #49A71
AND
SERVICE WRENCH)
SUCTION LINE SERVICE VALVE (VALVE
CLOSED)
INLET
(FROM INDOOR COIL)
OUTLET
(TO
COMPRESSOR)
KNIFE
EDGE
SEAL
SCHRADER VALVE
OPEN TO LINE SET
WHEN VALVE IS CLOSED
(FRONT SEATED)
SERVICE PORT
SERVICE
PORT
CAP
(VALVE
FRONT SEATED)
SNAP RING
STEM
CAP
OUTLET
(TO
COMPRESSOR)
KNIFE EDGE SEAL
INLET
(FROM INDOOR COIL)
INSERT
HEX WRENCH HERE
(PART #49A71 AND
SERVICE
WRENCH)
To Access Schrader Port:
1− Remove service port cap with an adjustable wrench.
2− Connect gauge to the service port.
3− When testing is completed, replace service port
cap. Tighten finger tight, then tighten an additional
1/6 turn.
To Open Suction Line Service Valve:
1− Remove stem cap with an adjustable wrench.
2− Using service wrench and 5/16" hex head extension
(part #49A71) back the stem out counterclockwise until
the valve stem just touches the retaining ring.
